Refrigerator evaporator



Feb 2L 1956 s. J. WILLIAMS, .JR

REFRIGERATOR EVAPORATOR 2 Sheets-Shee l Filed Dec. 11, 1952 Jizmfff S cf Williams/efr,

Feb. 21, 1956 s. J. WILLIAMS, JR

REFRIGERATOR EVAPORATOR Filed Dec. ll, 1952 2 Sheets-Sheet 2 f, f ,jf/,f

United States Patent() 2,735,280 REFRIGERATOR VEll/'APORAL'IR ISi I. 'Williams, '.lr., Evansville, intl., 4 assignor to 4Inter. national Harvester Company, va 'corporation .of New 'Jersey Application December 11, 1952,'SerialfNo. 325,323

2 Claims. `(Cl. v62-1-'26) This invention relates generally torefrigerator evaporators and more `specifically to improved refrigerator evaporators which When mounted in a refrigerator -will eili- .ciently and effectively function during both the refrigeration cycle and the defrost cycle ofthe refrigerator.

lt is an object of vthis .invention to provide anevaporater vwhich will functionto etliciently refrigerate a com- Vpartment of a refrigerator and which may be efficiently defrosted to melt accumulations of frost which will efec- 4tively-and rapidly drain from the surfaces of thejevapora- IOI.

lt is another object of this inventionto provide an evaporator `in a refrigerator which will eticiently refrigerate different 4portions of va refrigerator compartment to different degrees.

It is afeature of this invention lthatfa length of serpentine tubing cooperates with atheader connected yto a plurality of. parallel tubes toformaportionof a refrigerator evaporator.

.It is another feature of this vinvention that two`1enrgths ofcapillarytubing are used to provide different ranges of temperature in a refrigerator evaporator.

.Other objects and .features vof `the invention `will be apparent upon a perusal of the followingspeciiication and -drawings,.of which:

l:Figure l is=apartialfrontplan view of a refrigerator .cabinet embodying the invention;

'Figure 2 is-a side plan `view of `the evaporator shown in Figure 1;

.Figure 3 is a top sectional view onthere'frigerator cabinet shown in Figure lembodying the invention;

'Figure 4 is a topsectional view ofa refrigerator cabinet showing another embodiment .of the invention; and

Figure 5 is a side plan .viewoftheevaporatorshown inFigure 4.

The present .embodiments -are `the .preferred .embodi- -ments but it is to be understood that :changes canibe made infthe presentembodiments by oneskilledin the art Without departing from the-spirit and scope ofthis invention.

,It is. advantageous that a refrigerator.evaporator'beso vconstructed as 4to providea maximum usable volumewithin the contines of the refrigerator lowtemperat'ure cornpartrnent for the storage of food. It is 'further advantageous -to fprovide arefrigerator evaporator .which will refrigerate certainportionsof ,the refrigerator evaporator to one degree and will Yrefrigerate other'portions of the :refrigerator,evaporator to other degrees. It isffurther advantageous. to provide a refrigeratorrevaporator which2 may b e rapidly defroste`d, which will not zpermit puddles `of ,watertto accumulate within Vthe conlnesfdf the evaporator,

and which will not permit defrost water to drain ontoany food disposed within the confines of the evaporator. This invention incorporates all of these advantages.

To describe the invention in detail, reference is first made to Figures 1-3. Part of a refrigerator cabinet 30 is shown in which a compartment 32 is defined by the inner liner 52. A refrigerator door 31 is pivotally mounted to the refrigerator cabinet 30 as can easily be seen in Figorator through .the outlet l `1r1. g-43 and vthe rods 4.5 4of the .base 35 ,provides .ecient ICC ure 3. Thecompartment'321is-divided-"by .atray 33. The tray 33 A'serves to collect the ltlefrostvwater dripping from the evaporator and also serves to define a freezer compartment in the upper portion of the refrigerator cabinet, as can easily be seen lin .Figure -1. The `evaporator .comprises a vertical rear .wall/'portion 34 and ahorizonta'l base 35. The rearwall portion .34 and the'rbase 35 are disposed at right angles'to each otherl and are maintained in thisnpositionby-the pair vof diagonal braces 36. The vertical rear `portion v34ji s positioned substantially adjacent tothe rear Wa11.ofthe innerliner `52, and thebase 3S is positioned substantially adjacent to the upper side of the tray 33. Thus it maybe seen that a maximum amount of the space within Athe inner linerjSZ above the tray 3'3`is usable for the'storage of food.

The rear wall portion -34 of the evaporator comprises an upper header 37, va'lower'header ,38, and a plurality of parallel tubes 39,. The parallel tubes =39 interconnect vthe upper header 37 .and the lower'header 38, as can easily be seen in Figure 1. .To the upper portion of theupper header '37 an outlet orsuctio'ntube 40 is connected.

pentine ,tubing '43 is formed .tov a reduced diameterto conneet'withY a capillarytube 44, The other end of the ser- Epentine tubing :43is extended and connected to the lower header SS at'theju'nction 41. A plurality of rods or wires 4S -are mounted to the upper surface of the ,serpentine tubing 43, ascaneasilyibe seen in vFigures Zand 3. The rods 45 are disposedparallel .to one `another andare also parallel to the longitudinal axis off Vthe lower header 38.

The rods 45 are mounted inthermaleontact with the serpentine tubing '43.

It is intended -that the capillary tube .44 he connected 'to the .outlet Y.s id'e .of a r.conventional refrigerator C011- denser V(not shown), Aandt is further intended `that fthe outlet tube 40 `be connected tothe,inlet-,side yof aconven- `tional refrigerator v.cotripressor (not shownl, thereby liquid refrigerant will Vbe supplied to .the Aevaporator ,through the capillary j44.and1refrigerant ,gaseswill .be Withdrawn jfrom 'the .evaporator through Ithe outlet .tube 40. 'ItmBythen-be ,seen Ithat liquid,refrigerant Willow through the "length 'of serpentine tubing, .through the lower .header 43,8, through the parallel tubes .3.9 to .the upperheader'37. .As heat from any foodplacediwithin the confines `of Vthe .evaporator ris ,conducted to .the rods .the rear wallportion ,3.410 `thetoutle'ttu'be .40. .Any food placed withinlthe coninesof Vthe evaporator adjacent ,to the rear wall 3,4 .wilLalso .conduct heat to the parallel Vtubes 39 of .thejrear .wall l.portionltl to cause theliquid .refrigerant .disposed .therein ,to .assume .a gaseous state,

which ,gases .wilLalso be. easily withdrawn from. the.. evap tube 40. .The .serpentine tubmeans for conducting heat from any food placed upon the base 35, While the specific construction of the rear wall 34 provides means for conducting heat from any food placed adjacent thereto and for conducting the gases formed in the base 3S of the evaporator. Thus it can be seen that any food placed within the confines of the evaporator will be etiiciently cooled. Now, when ipositioned thereon, food placed adjacent to the rear wall portion 34. Due 'Y to the construction of the rear wall portion 34, suicient the evaporator has accumulated a certain amount of frost upon the surfaces thereof, and is defrosted by any conventional method, the accumulated frost will be melted and the water thereby formed will drip from the rear wall portion 34 and the base 35. The defrost water will dripY into the tray 33 and may be removed therefrom by any conventional method (not shown). No puddles will accumulate upon the base 35 due to the specific structure of the base 35, as the Water will drip between the rods 4S, and also will easily drip from the serpentine tubing 43. The defrost water from the rear wall portion 34 will ow downward along the parallel tubes 39 to the lower header 38, and will drip from the lower header 38 into the tray 33. It may then be easily seen that no defrost water will drip upon any food disposed within the freezer compartment. Further, because any food disposed within the freezer compartment will be positioned upon the rods 4S a minimum amount of defrosting of any frozen food placed thereon will result.

To describe the embodiment shown in Figures 4 and 5, reference is made thereto. This embodiment is identical to the embodiment shownin Figures 1 through 3 .except for the inlet and outlet tubes of the base 35 and the rear wall portion 34. The various parts of the embodiment shown in Figures 4 and 5 are numbered vwith the same numbers used in Figures 1 through 3 where these parts have functions identical to the functions described above for those identically numbered parts. One end of the serpentine tubing 43 is extended to form an outlet tube 54. The other end of the serpentine tub- -ing 43 is connected to a length of capillary tubing 51 or tubing 51 of a substantially reduced diameter. The other end of the capillary tubing 51 is connected to the lower header 38. A second length of capillary tubing 50 is connected to the upper surface of the upper header 37 to form an inlet tube. It is intended that the capillary tubing 50 be connected to the outlet side of a conventional refrigerator condenser (not shown), and that the outlet tube 54 be connected to the inlet side of a conven- 'tional refrigerator compressor (not shown). It may then be seen that liquid refrigerant will enter the capillary tube 50, will iiow into the `upper header 37, will tiow through the various parallel tubes 39 into the lower lheader 38, will ow through the capillary tubing 51 into the serpentine tubing 43. This will result in a substantially greater difference in pressure between the ends of lthe serpentine tubing 43 as compared to the inlet and outlet of the rear wall portion 34. Thus the liquid refrigerant will evaporate more rapidly in the base 3S than in the rear Wall base 35 will have a portion 34 and, consequently, the greater cooling effect upon any food than the cooling eifect upon any area is provided for an effective refrigeration of any food placed adjacent to the rear Wall portion 34. It may then be easily seen that the afore-described construction provides an evaporator which will eiciently serve to cool any food placed within the freezer compartment.

This evaporator may be defrosted in any conventional manner, and as previously described due to the construction of the base 35 and the rear wall portion 34, the

defrost water will be electively drained from the evaporator into the tray 33 Vwithout the formation of puddles of water within the confines of the evaporator, and without the dripping of any defrost water upon any food placed within the contines of the evaporator. Also, since the base 35 provides a greater cooling eifect than the rear wall portion 34, more frost will accumulate upon the surface of the base 35 than will accumulate upon the rear wall portion 34. Because of the specific construction of the base 35, as described above, this additional frost will be efficiently removed from the base 35 when the evaporator is defrosted.

Having described the invention, what is considered new and desired to be protected by Letters Patent is:

1. An evaporator for a refrigerator comprising a horizontally disposed base portion and a vertically disposed rear wall portion, said rear wall portion comprising an upper and a lower header and a plurality of parallel tubes interconnecting said headers, said base portion comprising a length of serpentine tubing having straight parallel sections interconnected by curved sections, said straight sections positioned in a horizontal plane including said lower header, said straight sections further positioned perpendicular to the longitudinal axis of said lower header, a plurality of rods mounted in a parallel spaced apart relationship to each other and to the longitudinal axis of said lower header on the upper surface of said serpentine tubing in thermal contact therewith, a pair of diagonal braces, each one of said braces mounted from one end of said rear wall portion to one end of said base portion, a length of capillary tubing connected between one end of said serpentine tubing and said lower header, a second length of capillary tubing connected to the upper surface of the upper header, whereby said second length of capillary tubing serves as an inlet tube for liquid refrigerant, and whereby the other end of said serpentine tubing forms an outlet tube.

2. In a refrigerator, an inner liner within said refrigerator, a horizontally disposed tray mounted in cooperation with said inner liner to thereby form a compartment positioned within said inner liner above said tray, evaporator means disposed within said compartment for refrigeration of said compartment comprising a horizontally disposed base portion and a vertically disposed rear wall portion, said baseportion having a horizontal area substantially equal to the horizontal arca of said tray, said rear wall portion having a vertical area substantially equal to the area of the rear portion of said inner liner above said tray, said rear wall portion comprising an upper and a lower header and a plurality of parallel tubes interconnecting said headers, ysaid base portion comprising a length. ofserpentine tubing having straight parallel sections interconnected by curved sections, said straight sections positioned in a horizontal plane including said lower header, said straight sections further po- Y inlet tube for liquid refrigerant, end of said serpentine tubing Y References Cited in the tile of this patent UNITED STATES PATENTS 2,004,692 Friedrich June 11, 1935 2,117,861 Steenstrup May 17, 1938 2,297,219 Hintze Sept. 29, 1942 2,473,508 Collins June 21, 1949 whereby said second length of cap- 

